I have this issue with WinXP SP2 computers, with OL 2003 SP3 + Adobe Reader 9.0 on them.
If I receive a PDF attachment and try to open it from inside its email, Adobe Reader freezes for a long while, then sometimes the PDF finally opens or I have to reboot the computer...
If the PDFs at last opens, if I close it and try again, it always opens at once.
If, instead of trying to open the attachment, I save it to disk, the issue does not appear.
Consider the issue appears not 100% of the times, I would say 70% and I experienced it on several PCs.
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